Energy absorbing element and manufacturing procedure thereof

Abstract

The present invention relates to an energy absorbing element intended to absorb the impact energy on vehicle doors constituted by a structure in hollow prismatic cells delimited by two bases parallel to their longitudinal axes, manufactured by extrusion, which results in a continuous piece from which by means of cutting the energy absorption element is obtained with a projection adapted to the form of the area to be protected. The disposition of the hollow prismatic cells is transversal to the direction of the force of the impact resulting in an energy absorption behaviour very close to optimal. The use of foams is also envisaged which allow the response curve of the absorbing element to be adapted without requiring the use of different extrusion dies.

1 . Energy absorbing element, of among the elements installable in the cavity of vehicle doors for the absorption of energy by impact by means of deformation characterised in that it is constituted by a honeycomb core formed by a regular stacking of cylindrical bodies of constant cross-section not closed on their ends, stacking limited by two bases, defined by means of planes or tangents to the cylindrical bodies with which it limits or secants to all or some of them according to the pattern used in the stacking, arranged one on each side of the core, where one of the bases is intended to rest on the unseen face of the door trim, and the opposite one, on that facing the unseen face of the door where the impact is received, the orientation of the axes of the cylindrical bodies of the core being parallel to the supporting bases, and both, bases supporting and axes of cylindrical bodies of the core, essentially perpendicular to the direction of the impact force.  
   
   
       2 . Energy absorbing element according to  claim 1  characterised in that one of its bases is constituted by a wall integrated in the core.  
   
   
       3 . Energy absorbing element according to  claim 1  characterised in that the bases are constituted by walls integrated in the core.  
   
   
       4 . Energy absorbing element according to  claim 1  characterised in that the core is configured by regular stacking of hollow cylindrical bodies of polyhedral cross-section.  
   
   
       5 . Energy absorbing element according to  claim 4  characterised in that the core is configured by stacking hollow cylindrical bodies of hexagonal cross-section in a honeycomb arrangement.  
   
   
       6 . Energy absorbing element according to  claim 1  characterised in that the core is configured by regular stacking of hollow cylindrical bodies of circular or elliptic cross-section.  
   
   
       7 . Energy absorbing element according to  claim 1  characterised in that some of the cavities of the core of the absorbing element are filled with foam.  
   
   
       8 . Energy absorbing element according to  claim 7  characterised in that it has the cavities filled with foam in alternate rows.  
   
   
       9 . Energy absorbing element according to  claim 7  characterised in that it has the rows of the core adjacent to one and the other base corresponding to a quarter of their volume with the cavities filled with foam.  
   
   
       10 . Energy absorbing element according to  claim 7  characterised in that it has the cavities filled with foam in half of the rows adjacent to one of the bases.  
   
   
       11 . Energy absorbing element according to  claim 7  characterised in that it has the cavities filled with foam in half of the intermediate rows.  
   
   
       12 . Procedure for manufacturing the energy absorbing element according to  claim 1 , wherein it is obtained by extrusion in plastic of a single continuous piece starting from which the final configuration is obtained of each element by cutting according to a perpendicular or oblique cut of the walls.  
   
   
       13 . Procedure for manufacturing the energy absorbing element according to  claim 10  characterised in that when the absorbing element has been cut from the extruded continuous piece, part of its cavities are filled with foam following a predetermined pattern.  
   
   
       14 . Procedure for manufacturing the energy absorbing element according to  claim 10  characterised in that the cutting of the absorbing element is carried out by means of a die.  
   
   
       15 . Procedure for manufacturing the energy absorbing element according to  claim 10  characterised in that the cutting of the absorbing element is carried out by means of a laser.  
   
   
       16 . Procedure for manufacturing the energy absorbing element according to  claim 10  characterised in that the cutting of the absorbing element is carried out by means of a jet of water at very high pressure.